Question

我使用CheckBoxList来显示一组业务单位。我想将选择限制为最多5项，如果用户选择第6项，那么我应该显示警告并取消选择第6项。

控制如下：

<asp:CheckBoxList ID="ckBLBusinessUnits" onclick="loader(this.id);" runat="server" AutoPostBack="True" Visible="false" OnSelectedIndexChanged="ckBLBusinessUnits_SelectedIndexChanged"></asp:CheckBoxList>

我正在使用的JS函数是：

function loader(controlID) {
    modal = document.getElementById('loadingImage');
    modal.style.display = "block";

    if (controlID == "ckBLBusinessUnits")
    {
        if (($('#ckBLBusinessUnits :checkbox:checked').length) > 5)
        {
            alert("Max 5 BU's can be selected");
//is it possible to uncheck here? I am unable to find any method to do so.
        }
    }
}

C＃如下：

protected void ckBLBusinessUnits_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (selectedValues.Count <= 5)
            {
                //Do something and then disable the loader.
                loadingImage.Style.Add("display", "none");
            }
            else if (selectedValues.Count > 5)
            {
               //is it possible to uncheck here? I am unable to find any method to do so.
            }

        }

Answer 1

这可能不是您要求的，但它可能适用于您的情况。每当所选项目总数为5时，禁用其他复选框，而不是取消选中该复选框，并显示您的提醒。

protected void CheckBoxList1_SelectedIndexChanged(object sender, EventArgs e)
{
        List<ListItem> SelectedItems = new List<ListItem>();

        foreach (ListItem ItemsSelected in CheckBoxList1.Items)
        {
            if (ItemsSelected.Selected)
                SelectedItems.Add(ItemsSelected);
        }

        if(SelectedItems.Count() == 5)
        {
            // Display alert

            foreach(ListItem item in CheckBoxList1.Items)
            {
                if(!SelectedItems.Contains(item))
                {
                    item.Enabled = false;
                }
            }
        } else
        {
            foreach (ListItem item in CheckBoxList1.Items)
            {
                item.Enabled = true;
            }
        }
}

CheckBoxList - 将选择限制为特定数字

1 个答案: